Cycle-frame.



No. 642,493. Patented Ian. 30, won. F., ROSENBERG.

CYCLE FRAME.

(Application filed Max. '1, 1898. Renewed Dec. 29, 1599'.

(No Model.)

NITED STATES AT'ENT Orrrcn.

FELIX ROSENBERG, OF BERLIN, GERMANY.

CYCLE-FRAM E.

SPECIFICATION forming part of Letters Patent No. 642,493, dated January 30, 1900.

Application filed March '7, 1898. Renewed December 29,1899. Serial No. 741,997. (No model.)

To all whom it may concern:

Be it known that I, FELIX ROSENBERG, a subject of the German Emperor, residing at Berlin, in the Kingdom of Prussia, German Empire, have invented certain new and useful Improvements in Cycle-Frames, of which the following is a full, clear, and exact specification.

The object of the presentinvention is a new construction of frame for cycles. Hitherto such frames have been constructed almost exclusively of tubing, whereby in addition to the high cost of manufacture of sufficiently rigid tubes the connection of the stays to one another causes considerable difficulty, there being at the same time a want of reliability.

xperiments have also been made to construct the frames of stamped plates; but the idea being always to imitate the tubular form equal strength to that of the latter has not been attained, and the advantages which the symmetrical cross-section offers have been lost. The frame forming the subject of the present invention deviates altogether from the tubular form. It consists of two peculiarly-shaped walls, which in the manner of a box-girder, such as is used in the construction of bridges, are arranged side by side and when connected by cross-plates offer a section of extreme rigidity. The peculiar construction of each separate wall consists in its being made as one piece of framework, statically calculated, with stiffening-ribs which surround the plate, particularly at the points of junction. Framework-walls of this kind, which possess such strength at the points of junction, have hitherto never been constructed for any purpose.

On the accompanying drawings one form of the new cycle-frame is shown.

Figure 1 shows a cycle constructed with such framing. Fig. 2 is a view of the fork of the rear wheel, while Figs. 3 to 8 show details to a larger scale.

The frame consists of two symmetrical plates of girder form A B, which carry the steering-tube O, saddle-support D, axis E of the chain-wheel, andaxis F of the rear wheel. Each plate forms a girder of bars and consists of one single piece, the section of each bar being of such dimensions as is necessary for bearing the strain on it. On the drawings, Fig. 3, a V-formed section is shown.

An essential feature of the framework-girder formed in one piece is that the stifieningribs, which afford rigidity against transverse strains to the fiat section of each individual wall, are bent around at all the points of j .unction, Fig. 8. In this way a construction is attained of such safety as can be secured neither by direct connection of the rods meeting at the points of junction nor by their connection with the help of joint-plates.

The connection of the two walls with each other (apart from those places where the steering-tube, the saddle-support, the axis of the crank and of the rear wheel have to be connected) is effected by means of cross-pieces G, which are preferably constructed by providing lugs projeotin g from each wall and securing them together by a rivet or the like, Figs. 3 and 4.

The forks of the rear wheel are formed simply by branching of the two walls, Fig. 2. The steering-tube is formed by each wall being made half-round and the union of both halves being effected by fianging. The saddle-supports may be secured to the stays of the frame by turned-over lugs, Fig. 5, and the nave for the axis of the pedal-crank formed by turning over the metal in tubular form at the lower points of junction, Fig. 6.

The walls may be cast, but preferably stamped and pressed, steel, aluminium, or other material being used. The material is first stamped fiat, and the edges are afterward turned over in a press in order to form stiffening-ribs. The lugs for transverse connection and also the step on the fork of the rear wheel are provided at the same time.

The frame formed in this manner has not only the advantage of costing much less in the manufacture than a tubular one,but adillactu're the construction of the steering-fork shown in Fig. 1 may be adopted. The fork here consists, likewise, of two walls in the form of framework and bent together to make a tube.

I claim- 1. A cycle-frame composed of two parts or sections, the bars forming each section being of channeled iron having lugs extending across and connected with corresponding lugs on the opposite bar, substantially as described.

2. A cycle-frame composed of two parallel sections, each composed of bars having in wardly-tnrned flanges overlapping lugs extending from the edges of the flanges of adjacent portions of the frame, and rivets connecting the overlapping lugs, substantiallyas described.

In Witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

FELIX ROSENBERG. Witnesses:

HERRMANN FRIEDLEINDER, W. HAUPT. 

